Aging is a natural phenomenon of living organisms and the skin is the most affected organ during aging process in human beings. Wrinkling of the skin is usually the result of degeneration of the tissue fibers, loss of subcutaneous fat and loss of normal fluid content. Skin wrinkles are grooves in the skin and it can be on the surface of the skin or quite in deep.
Facial wrinkles of the upper one third of the face are common cosmetic concern and are caused by over activity of the underlying facial musculature in principle. Exposure to the sun induces clinical and histological changes to the skin, commonly called photo aging. Aging and photo aging may be manifested as wrinkles, skin roughness and dryness, irregular pigmentation and brown spots.
Wrinkle formation in the skin following long-term exposure of ultraviolet B irradiation is accompanied by decrease in skin elasticity and the curling of elastic fibers in the dermis. Quantitative and qualitative changes in dermal collagen and elastin occur in response to chronic ultraviolet (UV) irradiation.
One of the approaches to protect the human skin from the harmful effects of ultra violet radiation is to use antioxidants as photoprotectives. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents.
Wrinkle formation in the skin is accompanied by decrease in skin elasticity and the curling of elastic fibers in the dermis. Elastase inhibitors suppress the elastase activity and prevent the damage of dermal elastic fibers and might abolish wrinkle formation associated with the loss of skin elasticity. Also, in aging the balance between collagen synthesis and collagen fragmentation is altered. Collagenase enzyme inhibitors are also known to have potential role in preventing wrinkle formation.
Hyaluronic Acid (HA), a natural glycosaminoglycan biopolymer, is found in every tissue of the human body. It has an enormous water binding capacity (up to 1,000 times its weight) and it forms high viscosity hydrated polymers. More than 50% of the total amount of body HA is present in skin (in dermis and epidermis). Hyaluronic acid is a basic building block of the dermis. It stabilizes the intercellular structures of connective tissues and forms the elastoviscous fluid matrix in which collagen and elastin fibers are embedded. It also promotes the renewal of keratinocytes and its ability to retain water helps in proper hydration of the skin. The amount of HA in the skin decreases with aging and photo aging process. Hyaluronidase is an enzyme that degrades HA resulting in reduced dermal hydration, disorganization of collagen and elastin fibers and increased skin wrinkling and folding. Hyaluronidase Inhibitors are known to have potential benefits in preventing and treating facial wrinkles.